... • Reserves used to protect endangered species
that are at risk from predation and human
influence
• Management of reserve must be carefully
considered
– Single large reserves or several small ones (SLOSS)
– Population size required for long term survival
...

... may render an environment hostile to a species. For example, temperatures may change and a species
may not be able to adapt. Food resources may be affected by environmental changes, which will
then cause problems for a species requiring these resources. Other species may become better
adapted to an ...

... include habitat loss, the
introduction of alien
species, overexploitation,
and breaking the
connectivity among
ecosystems.
• Deforestation and
draining wetlands can
result in habitat loss.
• Zebra Mussels
...

... extinction is generally considered to be the death of the
last individual of that species. In species which
reproduce sexually, extinction of a species is generally
inevitable when there is only one individual of that
species left, or only individuals of a single sex.
Extinction is not an unusual ev ...

... has been identified to be in danger of
extinction throughout all or a significant
part of its range, and that is under protection
by regulations or conservation measures.
 A threatened species is a species that has
been identified to be likely to become
endangered in the foreseeable future.
...

... largely ineffective. The passenger pigeon, which effectively became extinct
through hunting in the late-nineteenth century, also shows the dangers of
extinction associated with open access.
While hunting or harvesting has been a major cause of extinction (or threats to
extinction) of many large anim ...

... o Massive impact from an asteroid or comet
o Competition for Resources: too many organisms fighting over the same food/water/etc.
o Inability to Adapt: cannot change with their changing environment
When species become extinct, the opportunity exists for another species to fill that
ecological hole ...

... • Individuals can adapt to a changing environment. These
adaptations are heritable.
– Reality: Inherited traits are passed from parents to offspring in a
species. A mutation is a change in traits that are adapted over
time and through generations of a species. These changes allow
species to survive ...

... fairly steady rate over geological time and is the result of normal evolutionary processes,
with only a limited number of species in an ecosystem being affected at any one time.
Mass Extinction: The extinction of a large number of species within a relatively short
period of geological time, thought ...

... days. The nymphs burrow down into the soil and develop there for 6-10 years. In their last spring before emergence,
the nymphs build a turret like structure from clay and leaf matter on the surface of the soil, which is believed to be
important for male mating calls.
Habitat: Areas between open gras ...

... • Extinction is hard to define
• Rule of thumb is that a species is extinct after no evidence of it exists for 50 years
• Cahow—rare seabird thought to be extinct since 1621, but rediscovered in 1906
and a breeding colony discovered in 1951 (Hunter, 2002)
• Ivory-billed Woodpecker - may be extinct i ...

Extinction debt

In ecology, extinction debt is the future extinction of species due to events in the past. Extinction debt occurs because of time delays between impacts on a species, such as destruction of habitat, and the species' ultimate disappearance. For instance, long-lived trees may survive for many years even after reproduction of new trees has become impossible, and thus they may be committed to extinction. Technically, extinction debt generally refers to the number of species in an area likely to go extinct, rather than the prospects of any one species, but colloquially it refers to any occurrence of delayed extinction.In discussions of threats to biodiversity, extinction debt is analogous to the ""climate commitment"" in climate change, which states that inertia will cause the earth to continue to warm for centuries even if no more greenhouse gasses are emitted. Similarly, the current extinction may continue long after human impacts on species halt.Extinction debt may be local or global, but most examples are local as these are easier to observe and model. It is most likely to be found in long-lived species and species with very specific habitat requirements (specialists). Extinction debt has important implications for conservation, as it implies that species may go extinct due to past habitat destruction, even if continued impacts cease, and that current reserves may not be sufficient to maintain the species that occupy them. Interventions such as habitat restoration may reverse extinction debt.Immigration credit is the corollary to extinction debt. It refers to the number of species likely to immigrate to an area after an event such as the restoration of an ecosystem.